Casement windows, i.e., those of the type that pivot between their open and closed positions on hinges located on one of their sides, have long enjoyed considerable popularity with the public for a variety of reasons. They are, for example, easy to operate since they are readily opened and closed by means of a generally L-shaped crankshaft handle which rotates the crankshaft of their operating mechanism, whereas two-sash, double-hung windows require considerable effort to slide the sashes past one another in the opening and closing process. Due to the reduced perimeters that must be sealed from the elements, casement windows are also capable of providing superior insulation to structures in which they are installed, compared to double-hung windows.
A disadvantage of casement windows, however, is that most require a window operating mechanism, typically located on the sill of the frame within which the windows are mounted. When so positioned, the operating handle used to operate the mechanism frequently extends beyond the opening in which the window is mounted, thereby interfering with window coverings such as blinds, curtains, drapes and the like, positioned thereover.
To overcome this difficulty the L-shaped, crank handles have often been supplanted by handles having a low-profile, "tee-shaped" configuration since the latter are more compact and do not extend outwardly from the window sufficiently far to interfere with window hangings. Frequently, however, interference of the type described is not discovered until after the crankshaft handles have been installed, necessitating replacement of the handles with those of the tee-type.
While the process of substituting the one type of handle for the other is a relatively simple matter; unfortunately, it has up to now often been difficult to find a tee-shaped handle correctly sized to fit the crankshaft of a particular window operator. In this regard, there are a substantial number of casement window manufacturers, using various window operators, and these have failed to standardize the dimensions of the crankshafts used with their respective window operators. Consequently, it is often difficult to know whether a particular tee-shaped handle being offered for sale is correctly sized to permit replacement of the kind contemplated by this invention.
One method sometimes used to make such a determination prior to actually purchasing a replacement handle involves the use of a sample ring to which are connected a number of representative tee-handles, each being dimensioned to fit a different handle-engagement gear associated with the crankshafts of the more common casement window operators. A would-be purchaser borrows the sample ring from the seller, leaving a security deposit therefore, and checks the window in question at the window's location to determine which of the handles is correct before returning the ring to the store and proceeding with the purchase. The process described is involved, however, and to that extent it is undesirable for both the purchaser and the seller.
A different approach involves the removal of the crank handle to be replaced by the owner thereof, and its matching to one of the sample handle-engagement gears kept at the store of the seller. Again, however, the process involved is one requiring advance preparation before an actual purchase can be made.